MSD 1 : SYSTEMS DESIGN REVIEW

1. Team P12472 : Solar Stirling Generator Room 09-4425 10 AM – 12 PM Friday, January 20th 2012 MSD 1 : SYSTEMS DESIGN REVIEW https://edge.rit.edu/content/P12472/public/Home http://en.wikipedia.org/wiki/File:Beta_stirling_animation.gif

2. Project Team and Attendees Team P12472 Phil Glasser – Lead Engineer, Electrical Engineer William Tierney – Mechanical Engineer Bryan Abbott – Mechanical Engineer Mike Scionti– Mechanical Engineer Dr. Alan Raisanen – Faculty Guide and Customer

3. Meeting Purpose • Overview of the project • Confirm Engineering Specifications and Customer Needs • Review concepts • Propose a design approach and confirm its functionality • Cross-disciplinary review: generate further ideas

4. Materials Reviewed • Project Description • Work Breakdown Structure • Project Plan • Customer Needs • Engineering Specifications • Concept Development • Proposed Design • Risk Assessment

5. Project Description • We wish to demonstrate a small portable Stirling cycle electrical generator system that can be used to power small portable USB electronics. • Stirling generators can use any heat sourceto produce power including geothermal, waste heat and in our case solar energy. • Although mechanically more complex than photovoltaic systems, stirling generator system efficiency can out perform photovoltaic system efficiency. • Our system will require the design of a solar collector component, a stirling engine component, and an electrical generator, power conditioner and power storage component.

6. Beta Stirling Cycle • The Beta Type Stirling Engine consists of one cylinder containing a displacer piston and a power piston, coupled to a flywheel. • The working fluid on the far side of the cylinder is heated by some external heat source and the opposite side is cooled by a heat sink or some method of heat rejection. • As the working fluid on the hot side expands, it pushes the power piston towards the cold end of the cylinder. • On the cold end the gas contracts , pulling the power piston back towards the hot side. • The displacer piston acts as a shuttle, moving hot gas towards the cold side and vice versa. • The power piston and displacer piston rods are linked to the flywheel 90 degrees out of phase , producing output power.

7. Work Breakdown Structure / Physical Decomposition

8. Function Tree

9. Function Tree cont.

10. Function Tree cont.

11. Project Plan – MSD 1

12. Project Plan

13. Project Plan

14. Customer Needs • USB Charger: Stirling generator must output power through a USB port. • Stirling Engine: Generator component must be powered by a heat engine utilizing the stirling cycle. • Solar Power: Stirling engine must obtain its heat energy from the sun. • Self Start: Stirling engine must start autonomously. • Low Maintenance: Stirling generator system must operate for one year, maintenance free. • Inexpensive: Project may not exceed the project budget. • Light Weight: Stirling generator assembly must be relatively portable and need exceed the weight requirement. • Safe: Stirling generator must not cause any damage to people or surroundings when operated.

15. Customer Needs cont.

16. Engineering Specifications • Power: Stirling generator must output at least 10 Watts of power when operating. • Voltage: Generator component must provide a nominal voltage of 5 Volts when operating. • Budget: Stirling generator assembly must be within the budget of $500. • Weight: Stirling generator assembly must be within the weight requirement of 20 pounds. • Mean Time Between Failures: Stirling generator system must operate for one year before requiring maintenance. • Weatherproof: Stirling generator must be able to withstand all weather conditions.

17. Concept Development Decision Matrices: • Engine Configuration – Alpha, Beta, Gamma, Free Piston, Rotary, Ringborn • Linkage – Standard 90 degree offset, Rhombic Drive • Motor – Brushless DC, Stepper, Handwound Flywheel • Battery – Nickel-Metal Hydride, Rechargeable Alkaline, Lithium Ion, Lead-Acid

18. Engine Configuration We are continuing with the Beta Type Stirling Engine http://en.wikipedia.org/wiki/Stirling_engine http://www.ohio.edu/people/urieli/stirling/engines/gamma.html http://www.bekkoame.ne.jp/~khirata/english/fpse.htm http://www.bekkoame.ne.jp/~khirata/english/mk_rot.htm http://www.moriya-press.com/illustrations/ringbom_patent.html

19. Linkages We are continuing with the 90 Degree Offset Crankshaft http://en.wikipedia.org/wiki/Stirling_engine

20. Motors We are continuing with the AC Stepper Motor http://www.edn.com/article/510206-Hardware_controlled_brushless_dc_motors_ease_the_burden_on_CPUs.php http://en.wikipedia.org/wiki/Stepper_motor http://www.waterfuelcell.org/phpBB2/viewtopic.php?t=800

21. Batteries We are continuing with the Nickel-Metal Hydride Battery http://www.batteryfacts.co.uk/BatteryTypes/index.html http://www.kollewin.com/blog/lead-acid-batteries/ http://www.daviddarling.info/encyclopedia/A/AE_alkaline_battery.html

22. Proposed Design

23. Proposed Design

24. Feasibility Analysis

25. Feasibility Analysis cont.

26. Feasibility Analysis cont.

27. Feasibility Analysis cont.

28. Feasibility Analysis cont. • 5 Volt Output, 2 Amps, 10 Watts • Assuming ~60% efficiency of the generator, 18W motor needed • Rectify ac stepper voltage to DC by mixing all the phases through diodes • Linear regulator or buck/boost to desired V for charge circuit and USB output • Drive motor to overcome generator torque

29. Estimated Budget

30. Risk Analysis

31. Risk Analysis cont.

32. Questions?